Aphasia
Conditions
Brief summary
This study aims to determine whether transcranial direct current stimulation (tDCS) paired with speech-language therapy is more beneficial than speech-language therapy alone in acute and chronic post-stroke aphasia.
Detailed description
This study aims to determine whether behavioral word-retrieval therapy coupled with anodal tDCS will improve the fluency and name retrieval performance of participants with post-stroke aphasia more efficiently and for greater duration than language therapy alone (i.e. in the sham condition). tDCS neuronal targets will be selected in this order: 1. left posterior superior-middle temporal gyrus (an area critical for word retrieval and word comprehension), 2. left posterior frontal areas found to be responsible for lexical selection if the first area is infarcted, or 3. right cerebellum (important for learning, and consistently activated in naming task) if both of the other areas are infarcted. The same areas will be stimulated during the first tDCS and sham periods. If the participant returns for a second period of tDCS and sham with language therapy, the right cerebellum will be stimulated (if it was the only uninfarcted target area investigators will stimulate this area again). For cerebellar stimulation, either anodal or cathodal will be used as studies show that anodal or cathodal stimulation has an effect on cognitive functions.
Interventions
Stimulation will be delivered by a battery-driven constant current stimulator. The electrical current will be administered to a pre-specified region of the brain not affected by the lesion(perilesional areas, right hemisphere or cerebellum). The stimulation will be delivered at an intensity of 2mA (estimated current density 0.04 mA/cm2; estimated total charge 0.048C/cm2) in a ramp-like fashion for a maximum of 20 minutes. Speech-language therapy will be oral and written naming.
Speech-Language therapy will be administered during sham stimulation. Current will be administered in a ramp-line fashion but after the ramping the intensity will drop to 0 mA. Speech-language therapy will be oral and written naming.
Sponsors
Johns Hopkins University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 90 Years
Healthy volunteers
No
Inclusion criteria
* Clinically diagnosed with with post-stroke aphasia and word-retrieval deficits * Premorbid speakers of English * Diagnosis will be based on neuropsychological testing, language testing (most commonly the Western Aphasia Battery), MRI and clinical assessment * Stroke size: any l * Location: Left hemisphere strokes only from any etiology. * Time since stroke onset: 1 day to 20 years.
Exclusion criteria
* uncorrected visual or hearing impairment by self report * other premorbid neurological disorder affecting the brain * any other language-based learning disorder or other neurodegenerative disorder such as Alzheimer's Disease or Primary Progressive Aphasia * premorbidly diagnosed with a developmental language disorder * Pregnant women will also be excluded
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Change in picture naming scores in trained and untrained items | Before and after 15 sessions of intervention (3 weeks) and at 2 weeks and 2 months follow-ups |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Philadelphia Naming Test: Picture naming of everyday objects, different from training set | Before and after 15 sessions of intervention (3 weeks) and at 2 weeks and 2 months follow-ups | — |
| Change in Written naming of objects and actions | Before and after 15 sessions of intervention (3 weeks) and at 2 weeks and 2 months follow-ups | The investigators will evaluate the absolute number as well as the percent change of the list of objects and actions assigned for intervention as trained and untrained items. |
| Change in working memory (digit span) | Before and after 15 sessions of intervention (3 weeks) and at 2 weeks and 2 months follow-ups | — |
| Change in verbal fluency | Before and after 15 sessions of intervention (3 weeks) and at 2 weeks and 2 months follow-ups | The investigators will use letter (F, A, S) and semantic fluency measures (animals, fruits and vegetables) and the investigators will measure how many were added or omitted at follow-up intervals. |
Countries
United States
Outcome results
None listed